Underneath The Red Tide in South Florida

On Sept 19, 2018 TISIRI's Joe Kistel had the opportunity to video document seafloor conditions offshore southwest Florida. The region has been plagued with an ongoing "Harmful Algae Bloom" crisis. The brief video below provides a visual summary of what was observed underwater at regions 20 to over 30 miles offshore.

The seafloor was covered in dead invertebrate animals including crabs, snails, sea stars, lobster, and more. Encrusting reef organisms including sponges, tunicates, and mussels were also found dead. A near lifeless underwater ocean was observed.

It is most likely a concentration of Red tide (Karenia brevis) organisms killed the fish in the area. Next, there was likely a massive die off of the red tide bloom and the dead dinoflagellates cells fell to the sea floor. Then an overwhelming decomposition event removed available oxygen from the surrounding water, killing the invertebrate lifeforms. Furthermore nutrients were released back into the water after the decomposition event which could have been lethal to seafloor inhabitants as well. Not to mention those nutrients are now back in the water and can refuel additional red tide blooms.

A big thanks to the following for making this expedition possible:
Katie Laakkonen - City of Naples
Chris Darco - Collier County
Jeremy Sterk - Earth Tech Environmental
Brian King - Collier County